Synthesis of bioadhesive hydrogels from chitin derivatives

Zhao, Xian; Kato, Koichi; Fukumoto, Yuhshi; Nakamae, Katsuhiko

doi:10.1016/s0143-7496(01)00003-3

Cited by 53 publications

(21 citation statements)

References 19 publications

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“…Also, the presence of higher amounts of both gelatin and glutaraldehyde may result in low swelling and low surface exposure. The polyampholytic structure of IPNs may have an additional effect on tissue adhesion, due to the formation of transitional physical crosslinks between cationic and anionic groups carried by network chains (18). Besides, with a large amount of strong hydrogen-bonding groups (-OH, -COOH, -NH 2 ) on polymer chains, IPNs could adhere to the mucus layer through hydrogen bridges (19).…”

Section: Amount Of Mucin Adsorbed (Q E )mentioning

confidence: 99%

Formulation and characterization of tramadol-loaded IPN microgels of alginate and gelatin: Optimization using response surface methodology

Kumar¹,

Singh²

2010

Acta Pharmaceutica

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Tramadol-loaded interpenetrating polymer network (IPN) alginate-gelatin (AG) microgels (MG) were prepared by the chemical cross-linking technique with glutaraldehyde as cross-linking agent and were optimized using response surfaces. A central composite design for 2 factors, at 3 levels each, was employed to evaluate the effect of critical formulation variables, namely the amount of gelatin (X 1 ) and glutaraldehyde (X 2 ), on geometric mean diameter, encapsulation efficiency, diffusion coefficient (D), amount of mucin adsorbed per unit mass (Q e ) and 50 % drug release time (t 50 ). Microgels with average particle size in the range of 44.31-102.41 mm were obtained. Drug encapsulation up to 86.5 % was achieved. MGs were characterized by FT-IR spectroscopy to assess formation of the IPN structure and differential scanning calorimetry (DSC) was performed to understand the nature of drug dispersion after encapsulation into IPN microgels. Both equilibrium and dynamic swelling studies were performed in pH 7.4 phosphate buffer. Diffusion coefficients and exponents for water transport were determined using an empirical equation. The mucoadhesive properties of MGs were evaluated in aqueous solution by measuring the mucin adsorbed on MGs. Adsorption isotherms were constructed and fitted with Freundlich and Langmuir equations. In vitro release studies indicated the dependence of drug release on the extent of cross-linking and the amount of gelatin used in preparing IPNs. The release rates were fitted to a power law equation and Higuchi's model to compute the various drug transport parameters, n value ranged from 0.4055 to 0.5754, suggesting that release may vary from Fickian to quasi-Fickian depending upon variation in the formulation composition.

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Section: Amount Of Mucin Adsorbed (Q E )mentioning

confidence: 99%

Formulation and characterization of tramadol-loaded IPN microgels of alginate and gelatin: Optimization using response surface methodology

Kumar¹,

Singh²

2010

Acta Pharmaceutica

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“…The central element of the hemodialysis instrument is a semi-permiable membrane which efficiently transports low molecular weight toxin metabolites without affecting plasma protein [2]. It is reported that the surface properties such as the balance of hydrophilicity/hydrophobicity, electrical charge of biomaterials surface, protein adsorption and selectivity active carrier materials surface are the important factors to affect the character of membranes [10]- [13].…”

Section: Introductionmentioning

confidence: 99%

Permeability of Urea in N-Carboxymethyl Chitosan-Poly (Vynilalcohol) Blend Membranes for Hemodialysis

Lusiana¹,

Siswanta²,

Mudasir³

et al. 2013

IJCEA

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Abstract-A series of membranes are prepared by solvent drying method, which were composed of N-carboxymehtyl chitosan blended with poly(vinyl alcohol) [N-CMC/PVA]. The N-CMC/PVA membranes showed improved strength properties and permeability for low-molecular weight compounds. This novel membranes exhibited good permeability properties for small molecules also indicated a decrease in protein adsorption on the surface of membrane. The structure and the morphology of the resulting membranes were characterized by FTIR. NMR, elementary analysis and scanning electron microscopy (SEM).

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“…Chitosan is an abundant and natural polysaccharide which presents some interesting and useful properties such as biocompatibility, biodegradability, non-toxicity, adsorption and adhesion properties and the ability to interact with different substances (like hydrophilic and hydrophobic drugs) [13,22,23]. These characteristics are extremely important for medical and pharmaceutical applications, namely for the development controlled drug release devices [13,24,25]. For ocular applications, it is also recognized that chitosan-based formulations present a prolonged precorneal residence time, an ability to increase solution viscosity and excellent mucoadhesive properties [26,27].…”

Section: Introductionmentioning

confidence: 99%

Supercritical solvent impregnation of ophthalmic drugs on chitosan derivatives

Braga

Pato

Silva

et al. 2008

The Journal of Supercritical Fluids

106

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In this work, three chitosan derivatives (N-carboxymethyl chitosan (CMC), N-carboxybutyl chitosan (CBC) and N-succinyl chitosan (SCC)) were impregnated with flurbiprofen (an anti-inflammatory drug) and timolol maleate (an anti-glaucoma drug), using a supercritical solvent impregnation (SSI) technique (and employing high pressure CO 2 and CO 2 + EtOH mixtures) in order to develop hydrogel-type ophthalmic drug delivery applications. Impregnation experiments were carried out from 9.0 up to 14.0 MPa, and at 303.0, 313.0 and 323.0 K. The resulting polymeric drug delivery systems, as well as other polymeric samples processed in CO 2 , were characterized by FTIR spectroscopy and scanning electron microscopy (SEM). Drug release kinetics studies were performed for all prepared systems. The effects of impregnation pressure and temperature on the release kinetics results were studied and compared to the traditional soaking impregnation method. For the same operational conditions, results confirmed that the three different (chemically and physically) polymeric structures conditioned the impregnation and the drug release processes. Despite the final released drug mass is always the result of the employed operational impregnation conditions and of the very complex relative specific interactions that may occur between all species present in the system (drugs, polymers, CO 2 and ethanol), results showed that, for N-carboxymethyl chitosan, the predominant effects in the impregnation process seemed to be the solubility of drugs in CO 2 and in CO 2 + EtOH mixtures, as well as the swelling and plasticizing effect of CO 2 and ethanol on the polymer. Finally, the SSI method proved to be a more efficient and "tunable" impregnation process than the traditional impregnation of drugs by a soaking method. Therefore, and using this "tunable" SSI method, these N-chitosan derivatives-based ophthalmic drug delivery systems can be easily and efficiently prepared taking in consideration the desired drug levels according to patients needs.

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Synthesis of bioadhesive hydrogels from chitin derivatives

Cited by 53 publications

References 19 publications

Formulation and characterization of tramadol-loaded IPN microgels of alginate and gelatin: Optimization using response surface methodology

Formulation and characterization of tramadol-loaded IPN microgels of alginate and gelatin: Optimization using response surface methodology

Permeability of Urea in N-Carboxymethyl Chitosan-Poly (Vynilalcohol) Blend Membranes for Hemodialysis

Supercritical solvent impregnation of ophthalmic drugs on chitosan derivatives

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